Etching resist composition, pattern forming method making use of the same, printed-wiring board and its production

Abstract

An etching resist composition containing at least a polymeric compound having an acid value of not less than 35, a base, and water, and having a viscosity of 10 centipoises or below.

Description

1. Field of the inventionThis invention relates to a novel composition having etching resist properties, a pattern forming method making use of the composition, a printed-wiring board and a process for producing the printed-wiring board.More particularly, this invention is concerned with printed-wiring board processing in which, in forming a copper printed-wiring pattern, a resist pattern for etching a copper-clad laminate is directly drawn on copper foil by ink-jet printing.2. Related Background ArtIn conventional subtractive processes used in printed-wiring board processing, wiring patterns are formed by preparing pattern films by means of a laser plotter in accordance with wiring pattern data outputted from a CAD (computer-aided design system), and etching copper foil by using a resist ink or a dry film resist.In such conventional processes, it is necessary to first form a pattern film, and to prepare a printing plate in the case when a resist ink is used or to take the steps of ...

AI Technical Summary

Problems solved by technology

The dry film process is a photographic process and, though promising a high precision, requires many steps, inevitably resulting in a reasonably high cost especially for the manufacture in small lot.

The resin applied to the surface of a copper-clad laminate by printing becomes insoluble to acidic etchants as a result of evaporation of volatile bases such as ammonia and also becomes not easily soluble to basic etchants to have resistance to etching solutions, so that it has etching resist properties.

Since, however, these solvents can be removed with difficulty and may affect resist properties, they may preferably be used in an amount as small as possible.